Static sounding device and method based on seabed drilling machine

Abstract

The invention belongs to the technical field of marine geological exploration, and provides a static sounding device and method based on a seabed drilling machine. The device is detachably connected into a drill pipe of a seabed drilling machine, and specifically comprises a hoisting unit, a driving unit, a penetration unit and a static sounding probe which are sequentially connected from top to bottom, the driving unit comprises a lead screw driving shaft, an inner rotating frameless motor and a shell which are sequentially arranged from inside to outside. During sounding, the rotor of the inward-rotating frameless motor rotates to drive the penetration sleeve and the static sounding probe to penetrate into the stratum so as to obtain related data. The internal rotation frameless motor is adopted, so that the number of parts is greatly reduced, and the complexity is reduced; and the size of the whole structure in the vertical direction is greatly reduced, and the penetration stroke of the static sounding probe can be increased within the effective stroke of the drill pipe.

Description

Technical Field

[0001] The present disclosure relates to the technical field of marine geological exploration, and in particular to a static penetration device and a penetration method based on a seabed drilling rig. Background Art

[0002] As a new type of submarine resource, submarine natural gas hydrates possess enormous reserves. Global reserves of submarine natural gas hydrates are twice as high as existing natural gas and oil reserves, offering broad development prospects. The exploration and development of submarine natural gas hydrate resources as an alternative energy source to natural gas and oil is of great significance.

[0003] At present, submarine drilling rig technology has significantly improved drilling efficiency and reduced costs by achieving deep-dive docking of drill pipes and pressure-maintained coring, and has become a key technical support for "reducing costs and increasing efficiency" in the exploration and development of natural gas hydrates. Geotechnical multi-parameter static penetration technology is widely used in bottom geotechnical exploration of hydrate-bearing areas due to its high precision and strong stability. This technology can accurately identify sediment types, hydrate occurrence states, and spatial distribution characteristics, providing key support for resource potential assessment. However, the process methods used in drilling sampling and static penetration technology are different. Static penetration technology requires a separate penetration system and cannot be matched with drilling sampling. This technical bottleneck limits the detection efficiency and data accuracy of hydrate exploration, and restricts the improvement of multi-parameter comprehensive analysis capabilities. Summary of the Invention

[0004] The present disclosure provides a static penetration device and a penetration method based on a seabed drilling rig, so as to at least solve the above technical problems existing in the prior art.

[0005] According to a first aspect of the present disclosure, a static penetration device based on a seabed drilling rig is provided, wherein the static penetration device is detachably connected to a drill pipe of the seabed drilling rig; the drill pipe comprises a spring-loaded retaining tube, a spring-loaded chamber, an outer tube, and a drill bit, which are sequentially connected from top to bottom; a seat ring is embedded in one end of the outer tube close to the spring-loaded chamber, and the inner diameter of the seat ring is smaller than the inner diameter of the drill pipe; the static penetration device comprises a hoisting unit, a driving unit, a penetration unit, and a static penetration probe, which are sequentially connected from top to bottom; wherein, The hanging unit includes a central shaft, a spring-loaded mechanism, an armored cable connected to the upper and lower ends of the central shaft, and a suspension connecting pipe; a suspension ring is provided at the lower end of the suspension connecting pipe, the outer diameter of the suspension ring is larger than the inner diameter of the seat ring, and the suspension ring is press-fitted to the top surface of the seat ring; the spring-loaded mechanism is wound around the central shaft, and the spring-loaded mechanism can be expanded outward under the action of an external force to engage with the spring-loaded chamber or contracted inward to disengage from the spring-loaded chamber, thereby realizing a detachable connection between the static penetration device and the drill pipe; The drive unit includes a screw drive shaft, an inner-rotating frameless motor, and a housing, which are arranged in sequence from the inside to the outside; the screw drive shaft is arranged at the center of the drive unit; the inner-rotating frameless motor includes a stator and a rotor, the stator is connected to the housing; the rotor is connected to the screw drive shaft, and is used to drive the screw drive shaft to rotate; The penetration unit includes a hollow screw, a hollow screw nut, a penetration sleeve, and an elastic spiral watertight cable; the elastic spiral watertight cable is arranged at the center of the penetration unit; the hollow screw is arranged on the outside of the elastic spiral watertight cable, and is connected to the screw drive shaft at the upper end, for rotating with the rotation of the screw drive shaft; a hollow screw nut and a penetration sleeve are provided on the outside of the hollow screw, and the lower end of the hollow screw nut is connected to the upper end of the penetration sleeve, for moving up and down with the rotation of the hollow screw to drive the penetration sleeve to move downward; the upper end of the static probing probe is respectively connected to the lower end of the penetration sleeve and the lower end of the elastic spiral watertight cable, for penetrating into the formation under the drive of the penetration sleeve to obtain relevant data, and driving the elastic spiral watertight cable to extend in the vertical direction to transmit data in real time.

[0006] In one embodiment, the stator and the housing are fixedly connected via a keyway.

[0007] In one embodiment, the rotor is fixedly connected to the screw drive shaft via a keyway.

[0008] In one embodiment, the driving unit further includes a motor retaining ring, which is provided at the upper end of the inner-rotating frameless motor and is used to limit the position of the inner-rotating frameless motor in the vertical direction.

[0009] In one embodiment, a thrust ball bearing is provided at each of the upper and lower ends of the screw drive shaft for bearing the axial force generated by the screw drive shaft during rotation.

[0010] In one embodiment, an upper end cover and a lower end cover are respectively provided at the upper end and the lower end of the shell for fixing and sealing the components of the drive unit.

[0011] In one embodiment, a first dynamic sealing ring and a second dynamic sealing ring are respectively provided between the screw drive shaft and the upper end cover and the lower end cover.

[0012] Specifically, the dynamic sealing ring is provided for sealing during a rotation process. The first dynamic sealing ring and the second dynamic sealing ring are provided as a first Glyd ring and a second Glyd ring respectively.

[0013] In one embodiment, a sealing ring is provided between the shell and the upper end cover for sealing between the shell and the upper end cover.

[0014] Specifically, the sealing ring is configured as an O-ring.

[0015] In one embodiment, the drive unit further includes a watertight connector, which is disposed through the upper end cover and the motor retaining ring and is used to supply power to the inner-rotating frameless motor and seal the drive unit.

[0016] In one embodiment, the hollow screw is fixedly connected to the screw drive shaft by bolts.

[0017] In one embodiment, the lower end of the hollow screw nut is connected to the upper end of the penetration sleeve via a thread.

[0018] In one embodiment, the upper end of the static penetration probe is connected to the lower end of the penetration sleeve via a threaded connection.

[0019] In one embodiment, the penetration unit further includes an outer support tube, which is disposed at the outermost side of the penetration unit; the upper end of the outer support tube is fixedly connected to the lower end of the shell by bolts.

[0020] In one embodiment, the penetration unit further includes a limit block disposed in the grooves on both sides of the outer support tube; the lower end of the limit block is connected to the upper end of the hollow screw nut to limit the axial displacement of the hollow screw nut.

[0021] Specifically, the lower end of the limiting block is fixedly connected to the upper end of the hollow lead screw nut by means of bolts.

[0022] In one embodiment, the penetration unit further includes a limiting sleeve, which is disposed between the penetration sleeve and the outer support tube and is used to limit the axial displacement of the penetration sleeve.

[0023] In one embodiment, the ejection mechanism includes an ejection tube and an ejection card.

[0024] Specifically, the structure of the spring-cage mechanism is similar to that of the conventional rope coring structure, and will not be described in detail here.

[0025] In one embodiment, the hanging unit further includes a fishing head, wherein the upper end of the fishing head is connected to the armored cable, and the lower end of the fishing head is connected to the upper end of the spring-loaded tube.

[0026] In one embodiment, the lower end of the spring-loaded tube is connected to the upper end of the suspension connecting tube.

[0027] According to a second aspect of the present disclosure, a penetration method of the static penetration device is provided, comprising the following steps: S1: lowering the static penetration device into the drill pipe of the seabed drilling rig via the armored cable until the suspension ring of the suspension connecting pipe is pressed onto the seat ring of the drill pipe and the spring-locking mechanism is engaged with the spring-locking chamber; S2: The power cord of the armored cable drives the inner rotating frameless motor to operate, wherein the stator remains fixed, the rotor rotates and drives the screw drive shaft to rotate, and further drives the hollow screw to rotate; the rotating hollow screw drives the hollow screw nut to move up and down, thereby driving the penetration sleeve and the static penetration probe to penetrate the formation below the drill pipe, and the static penetration probe obtains relevant data; at the same time, the elastic spiral watertight cable extends in the vertical direction as the static penetration probe is penetrated, so as to transmit the relevant data in real time; S3: After the operation is completed, the rotor rotates in the opposite direction to recover the penetration sleeve and the static penetration probe; after the recovery is completed, the armored cable is used to lift the static penetration device upward. During the lifting process, the ejection mechanism retracts inward and disengages from the ejection chamber, thereby lifting the static penetration device to the seabed drilling rig platform.

[0028] According to an embodiment of the present disclosure, there are at least the following beneficial effects: An internally rotating frameless motor (internal rotor frameless torque motor) is a frameless motor with an internal rotor and an external stator. The rotor is directly integrated onto the load shaft, eliminating traditional moving parts (such as couplings and reducers), reducing its size and making it suitable for space-constrained applications. The rotor's mass is concentrated at the center of rotation, resulting in low inertia and faster acceleration / deceleration, significantly improving system response speed and enabling more precise motion control. The drive unit disclosed herein utilizes an internally rotating frameless motor. Because this structure is hollow, compared to the previous "bevel gear set transmission," the transmission cable (elastic spiral watertight cable) of the static penetration probe can be directly connected to the armored cable along the hollow channel, significantly reducing the number of parts required and complexity. Furthermore, because this structure is significantly smaller in the vertical direction, the penetration stroke of the static penetration probe can be increased within the effective stroke of the drill pipe.

[0029] Furthermore, compared to traditional scientific research vessel exploration platforms, subsea drilling rigs offer advantages such as flexible deployment, minimal platform requirements, and a high degree of automation. Downhole geotechnical survey technology can directly test various reservoir parameters in situ, with high accuracy and reliability. Through multi-sensor integration and optimized deployment and recovery methods, the in situ mechanical properties of the reservoir and the distribution characteristics of hydrates can be accurately determined. This disclosure integrates in-situ survey and sampling technologies on subsea drilling rigs, further enriching my country's marine hydrate exploration methods, reducing costs and increasing efficiency, and providing technical support for the development of marine natural gas hydrates in my country.

[0030] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood by reading the detailed description below with reference to the accompanying drawings, in which several embodiments of the present disclosure are shown by way of example and not limitation, wherein: In the drawings, the same or corresponding reference numerals denote the same or corresponding parts.

[0032] Figure 1 A schematic structural diagram of a static penetration device in an embodiment of the present disclosure is shown; Figure 2 shows a longitudinal cross-sectional view of the structure of the drive unit in an embodiment of the present disclosure; Figure 3 A longitudinal cross-sectional view of the structure of the penetration unit in an embodiment of the present disclosure is shown; Figure 4 This disclosure shows Figure 1 An enlarged view of the longitudinal cross-sectional structure of part A.

[0033] Description of the numbers in the figure: 11-Armored cable; 12-Fishing head; 131-Spring-clamp tube; 132-Spring-clamp; 14-Suspension connecting tube; 141-Suspension ring; 2-Drive unit; 210-Screw drive shaft; 211-Stator; 212-Rotor; 213-Casing; 214-Motor retaining ring; 215-First thrust ball bearing; 216-Second thrust ball bearing; 217-Upper end cover; 218-Lower end cover; 220-First dynamic sealing ring; 221-Second dynamic sealing ring; 222-Sealing ring; 223-Watertight connector; 3-Penetration unit; 310-Hollow screw; 311-Hollow screw nut; 312-Penetration sleeve; 313-Elastic spiral watertight cable; 314-Outer support tube; 315-Limiting block; 316-Limiting sleeve; 4-Static penetration probe. DETAILED DESCRIPTION

[0034] To make the purposes, features, and advantages of the present disclosure more apparent and understandable, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without creative work shall fall within the scope of protection of the present disclosure.

[0035] Based on the structure and operating mode of the coring drill pipe of a submarine drilling rig, this paper has designed a downhole geotechnical multi-parameter in-situ detection device, designed to meet the requirements of a static cone penetration probe penetrating seafloor sediments at a constant speed (2 cm / s). This design utilizes a stable downhole electric-driven lead screw as the core penetration mechanism, ensuring precise control and low-disturbance penetration. It also enables real-time upload of static cone penetration probe data and precise matching of formation depth. The following describes the device in detail.

[0036] Example This embodiment provides a static penetration device based on a seabed drilling rig, which is detachably connected to the drill pipe of the seabed drilling rig; the drill pipe includes a spring-loaded retaining tube, a spring-loaded chamber, an outer tube and a drill bit connected in sequence from top to bottom, and a seat ring is embedded in the end of the outer tube near the spring-loaded chamber, and the inner diameter of the seat ring is smaller than the inner diameter of the drill pipe; see Figure 1 The static penetration device includes a hanging unit, a driving unit 2, a penetration unit 3 and a static penetration probe 4 connected in sequence from top to bottom; wherein, The hanging unit includes a central shaft, a snap-in mechanism, an armored cable 11 connected to the upper and lower ends of the central shaft, a suspension connecting pipe 14, and a fishing head 12. Specifically, a suspension ring 141 is provided at the lower end of the suspension connecting pipe 14. The outer diameter of the suspension ring 141 is larger than the inner diameter of the seat ring, and the suspension ring 141 is pressed against the top surface of the seat ring. The snap-in mechanism is wound around the central shaft. Under the action of an external force, the snap-in mechanism can be expanded outward to engage with the snap-in chamber or contracted inward to disengage from the snap-in chamber, thereby realizing a detachable connection between the static penetration device and the drill pipe. The snap-in mechanism mainly includes a snap-in tube 131 and a snap-in 132. The above-mentioned engagement or disengagement is realized by the snap-in 132. The snap-in 132 is expanded outward to engage with the snap-in chamber and contracted inward to disengage from the snap-in chamber. The specific structure of the snap-in mechanism is similar to the snap-in structure in a conventional rope coring structure and will not be described in detail here. The upper end of the fishing head 12 is connected to the armored cable 11 , and the lower end is connected to the upper end of the spring-loaded tube 131 ; the lower end of the spring-loaded tube 131 is connected to the upper end of the suspension connecting tube 14 .

[0037] The specific structure of the drive unit 2 is as follows Figure 2As shown, the drive unit 2 includes, from inside to outside, a screw drive shaft 210, an inner-rotating frameless motor, and a housing 213. The screw drive shaft 210 is located at the center of the drive unit 2, and a first thrust ball bearing 215 and a second thrust ball bearing 216 are provided at the upper and lower ends of the screw drive shaft 210, respectively, to withstand the axial force generated by the screw drive shaft 210 during rotation. The inner-rotating frameless motor includes a stator 211 and a rotor 212. The stator 211 is fixedly connected to the housing 213 via a keyway to generate a rotating magnetic field to drive the rotor 212 to rotate. The rotor 212 is fixedly connected to the screw drive shaft 210 via a keyway to drive the screw drive shaft 210 to rotate. A motor retaining ring 214 is provided at the upper end of the inner-rotating frameless motor to limit the vertical position of the inner-rotating frameless motor. An upper end cap 217 is provided at the upper end of the housing 213, and a lower end cap 218 is provided at the lower end to secure and seal the various components of the drive unit 2. A first dynamic seal 220 and a second dynamic seal 221 are respectively provided between the screw drive shaft 210 and the upper and lower end caps 217 and 218, respectively, to seal during rotation. The first dynamic seal 220 is configured as a first Glyd ring, and the second dynamic seal 221 is configured as a second Glyd ring. A seal 222 is provided between the housing 213 and the upper end cap 217, configured as an O-ring, to provide a seal between the two. The drive unit 2 also includes a watertight connector 223, which extends through the upper end cap 217 and the motor retaining ring 214 and is used to power the inner-rotating frameless motor and seal the drive unit 2.

[0038] The structure of penetration unit 3 is as follows Figure 3 As shown, the penetration unit 3 includes a hollow screw 310, a hollow screw nut 311, a penetration sleeve 312, and an elastic spiral watertight cable 313. The elastic spiral watertight cable 313 is arranged at the center of the penetration unit 3; the hollow screw 310 is arranged outside the elastic spiral watertight cable 313 and is connected to the screw drive shaft 210 at the upper end (see Figure 4), which is used to rotate with the rotation of the screw drive shaft 210; a hollow screw nut 311 and a penetration sleeve 312 are provided on the outside of the hollow screw 310, and the lower end of the hollow screw nut 311 is connected to the upper end of the penetration sleeve 312 by a threaded form, and is used to move up and down with the rotation of the hollow screw 310 to drive the penetration sleeve 312 to move downward; the upper end of the static sounding probe 4 is connected to the lower end of the penetration sleeve 312 by a threaded form, and the upper end of the static sounding probe 4 is also connected to the lower end of the elastic spiral watertight cable 313, which is used to penetrate into the formation under the drive of the penetration sleeve 312 to obtain relevant data, and drive the elastic spiral watertight cable 313 to extend in the vertical direction to transmit data in real time. The penetration unit 3 further includes an outer support tube 314, a stop block 315 and a stop sleeve 316; the outer support tube 314 is arranged at the outermost side of the penetration unit 3; the upper end of the outer support tube 314 is fixedly connected to the lower end of the shell 213 by bolts (see Figure 4 Limit blocks 315 are positioned in grooves on both sides of the outer support tube 314. The lower end of the limit blocks 315 is fixedly connected to the upper end of the hollow screw nut 311 via bolts, thereby limiting the axial displacement of the hollow screw nut 311. A limit sleeve 316 is positioned between the penetration sleeve 312 and the outer support tube 314 to limit the axial displacement of the penetration sleeve 312.

[0039] The penetration method of the above-mentioned static penetration device is as follows: (1) After the seabed drilling rig has opened a hole, the static penetration device is lowered into the drill pipe of the seabed drilling rig through the armored cable 11 using the underwater winch device until the suspension ring 141 of the suspension connecting pipe 14 is pressed against the seat ring of the drill pipe, and the spring-loaded mechanism is engaged with the spring-loaded chamber (specifically, the spring-loaded mechanism 132 is engaged with the spring-loaded chamber).

[0040] (2) The power line of the armored cable 11 drives the inner frameless motor to work, wherein the stator 211 remains fixed, generates a rotating magnetic field, drives the rotor 212 to rotate, and the rotating rotor 212 drives the screw drive shaft 210 to rotate, further driving the hollow screw 310 to rotate; the rotating hollow screw 310 drives the hollow screw nut 311 to move up and down, thereby driving the penetration sleeve 312 and the static penetration probe 4 to penetrate the stratum below the drill pipe at a constant speed, and the static penetration probe 4 obtains relevant geotechnical parameter data; during the penetration process, the elastic spiral watertight cable 313 extends in the vertical direction as the static penetration probe 4 penetrates, so as to transmit the above data in real time.

[0041] (3) After the operation is completed, the rotor 212 rotates in the opposite direction to recover the penetration sleeve 312 and the static penetration probe 4. After the recovery is completed, the static penetration device is lifted upward by the armored cable 11. During the lifting process, the spring-loaded mechanism retracts inward (specifically, the spring-loaded mechanism 132 retracts inward) and disengages from the spring-loaded chamber, thereby lifting the static penetration device to the seabed drilling rig platform.

[0042] In summary, the internal rotating frameless motor adopted in the present invention (suitable for applications with limited space, the rotor mass is concentrated at the center of rotation, the inertia is small, the acceleration / deceleration is faster, the system response speed is improved, and more precise motion control can be achieved) is a hollow structure. Compared with the previously designed "bevel gear set transmission", the transmission cable of the static penetration probe can be directly connected to the armored cable along the hollow channel, which greatly reduces the parts setting at the structure and reduces the complexity. In addition, the size of the structure in the vertical direction is greatly reduced, which can increase the penetration stroke of the static penetration probe within the effective stroke of the drill pipe.

[0043] Compared to traditional research vessel exploration platforms, subsea drilling rigs offer advantages such as flexible deployment, minimal platform requirements, and a high degree of automation. Downhole geotechnical survey technology allows for direct in-situ testing of reservoir parameters with high accuracy and reliability. Through multi-sensor integration and optimized deployment and recovery methods, the in-situ mechanical properties of the reservoir and the distribution of hydrates can be accurately determined. This disclosure integrates in-situ survey and sampling technologies on a subsea drilling rig, further enriching my country's marine hydrate exploration capabilities, reducing costs and increasing efficiency, and providing technical support for the development of natural gas hydrates in my country's oceans.

[0044] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions of this disclosure can be achieved, and this document is not limited here.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. Throughout the present disclosure, "plurality" means two or more, unless otherwise specifically defined.

[0046] The above description is merely a specific embodiment of the present disclosure, but the scope of protection of the present disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this disclosure should be included in the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be based on the scope of protection of the claims.

Claims

1. A static penetration device based on a seabed drilling rig, characterized in that: The static penetration device is detachably connected to the drill pipe of the seabed drilling rig; the drill pipe includes a spring-loaded retaining tube, a spring-loaded chamber, an outer tube and a drill bit connected in sequence from top to bottom, and a seat ring is embedded in one end of the outer tube close to the spring-loaded chamber, and the inner diameter of the seat ring is smaller than the inner diameter of the drill pipe; the static penetration device includes a hoisting unit, a driving unit, a penetration unit and a static penetration probe connected in sequence from top to bottom; wherein, The hanging unit includes a central shaft, a spring-loaded mechanism, an armored cable connected to the upper and lower ends of the central shaft, and a suspension connecting pipe; a suspension ring is provided at the lower end of the suspension connecting pipe, the outer diameter of the suspension ring is larger than the inner diameter of the seat ring, and the suspension ring is press-fitted to the top surface of the seat ring; the spring-loaded mechanism is wound around the central shaft, and the spring-loaded mechanism can be expanded outward under the action of an external force to engage with the spring-loaded chamber or contracted inward to disengage from the spring-loaded chamber, thereby realizing a detachable connection between the static penetration device and the drill pipe; The drive unit includes a screw drive shaft, an inner-rotating frameless motor, and a housing, which are arranged in sequence from the inside to the outside; the screw drive shaft is arranged at the center of the drive unit; the inner-rotating frameless motor includes a stator and a rotor, the stator is connected to the housing; the rotor is connected to the screw drive shaft, and is used to drive the screw drive shaft to rotate; The penetration unit includes a hollow screw, a hollow screw nut, a penetration sleeve, and an elastic spiral watertight cable; the elastic spiral watertight cable is arranged at the center of the penetration unit; the hollow screw is arranged on the outside of the elastic spiral watertight cable, and is connected to the screw drive shaft at the upper end, for rotating with the rotation of the screw drive shaft; a hollow screw nut and a penetration sleeve are provided on the outside of the hollow screw, and the lower end of the hollow screw nut is connected to the upper end of the penetration sleeve, for moving up and down with the rotation of the hollow screw to drive the penetration sleeve to move downward; the upper end of the static probing probe is respectively connected to the lower end of the penetration sleeve and the lower end of the elastic spiral watertight cable, for penetrating into the formation under the drive of the penetration sleeve to obtain relevant data, and driving the elastic spiral watertight cable to extend in the vertical direction to transmit data in real time.

2. The static penetration device according to claim 1, characterized in that: In the drive unit, the stator and the housing are fixedly connected via a keyway; and the rotor and the screw drive shaft are fixedly connected via a keyway.

3. The static penetration device according to claim 1, characterized in that: The driving unit further includes a motor retaining ring, which is arranged at the upper end of the inner-rotating frameless motor and is used to limit the position of the inner-rotating frameless motor in the vertical direction.

4. The static penetration device according to claim 1, characterized in that: A thrust ball bearing is provided at each of the upper and lower ends of the screw drive shaft for bearing the axial force generated by the screw drive shaft during rotation.

5. The static penetration device according to claim 1, characterized in that: An upper end cover and a lower end cover are respectively provided at the upper end and the lower end of the shell for fixing and sealing the components of the drive unit.

6. The static penetration device according to claim 1, characterized in that: The hollow screw is fixedly connected to the screw drive shaft by bolts; The lower end of the hollow screw nut is connected to the upper end of the penetration sleeve through a threaded connection; The upper end of the static penetration probe is connected to the lower end of the penetration sleeve through a threaded connection.

7. The static penetration device according to claim 1, characterized in that: The penetration unit further comprises an outer support tube, a limit block and a limit sleeve; the outer support tube is arranged at the outermost side of the penetration unit; the upper end of the outer support tube is fixedly connected to the lower end of the shell by bolts; The limit blocks are arranged in the grooves on both sides of the outer support tube; the lower end of the limit block is connected to the upper end of the hollow screw nut, and is used to limit the axial displacement of the hollow screw nut; The limiting sleeve is arranged between the penetration sleeve and the outer support sleeve, and is used to limit the axial displacement of the penetration sleeve.

8. The static penetration device according to claim 1, characterized in that: In the hanging unit, the ejection mechanism includes an ejection tube and an ejection card; The hanging unit further includes a fishing head, the upper end of which is connected to the armored cable, and the lower end of which is connected to the upper end of the spring-loaded tube.

9. The static penetration device according to claim 8, characterized in that: The lower end of the spring-locking tube is connected to the upper end of the suspension connecting tube.

10. The penetration method of the static penetration device according to any one of claims 1 to 9, characterized in that: The steps include: S1: lowering the static penetration device into the drill pipe of the seabed drilling rig via the armored cable until the suspension ring of the suspension connecting pipe is pressed onto the seat ring of the drill pipe and the spring-locking mechanism is engaged with the spring-locking chamber; S2: The power cord of the armored cable drives the inner rotating frameless motor to operate, wherein the stator remains fixed, the rotor rotates and drives the screw drive shaft to rotate, and further drives the hollow screw to rotate; the rotating hollow screw drives the hollow screw nut to move up and down, thereby driving the penetration sleeve and the static penetration probe to penetrate the formation below the drill pipe, and the static penetration probe obtains relevant data; at the same time, the elastic spiral watertight cable extends in the vertical direction as the static penetration probe is penetrated, so as to transmit the relevant data in real time; S3: After the operation is completed, the rotor rotates in the opposite direction to recover the penetration sleeve and the static penetration probe; after the recovery is completed, the armored cable is used to lift the static penetration device upward. During the lifting process, the ejection mechanism retracts inward and disengages from the ejection chamber, thereby lifting the static penetration device to the seabed drilling rig platform.

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